Liquid purifying system



LIQUID PURIFYING SYSTEM Filed Sept. 9, 1966 m m m E P ww E, s L J n J w a w 5 l- A L M) um, 5 m m /l um? g L NQRQNZQU vm. A MFA Imm. r i .uMNmQ MRM unsb fx ov e l wm? Nw.. J/\.

United States Patent 3,357,161 LIQUID PURIFYING SYSTEM Louis Starr and Allan L. Kaplan, Oak Park, and Lewis J.

Cox, Pontiac, Mich., assign'ors, by mesne assignments,

of one-half each to said Starr and said Kaplan, Oak

Park, Mich.

Filed Sept. 9, 1966, Ser. No. 578,322 9 Claims. (Cl. 55-189) ABSTRACT OF THE DSCLOSURE An accumulator where liquid to be purified is exposed to a vacuum for removing gaseous impurities from the liquid, and the purified liquid is supplied to a utilization device which is also evacuated. Liquid is supplied to the accumulator from liquid supply means via a storage receptacle which communicates with the accumulator. Vacuum is applied to the accumulator by a vacuum pump via a trap which is connected to the accumulator. The trap, the accumulator and the utilization device are connected to each other suchl thatl a single vacuum pump serves to evacuate all of these elements of the purifying system.

This invention relates to hydraulic systems, and more particularly to a purifying system for removing gaseous impurities from a hydraulic liquid which is then used to fillv a utilization device such as the master cylinder in an automotive brake system.

In order to obtain the best results in a braking system, it is desirable that the hydraulic oil filling the master cylinder be relatively free of gaseous impurities such as air and water vapor, for' example. Inother words, it is desirable to have the hydraulic oil in the master cylinder as solid and homogeneous as possible.

The present invention provides a purifying system which effectively removes gaseous impurities from a liquid for use in a brake system or other utilization device. In a particular embodiment, unpurified liquid is supplied to a cylinder which is in communication with an accumulator in which the liquid is exposed to avacuum so that gaseous impurities are drawn out of the liquid into the evacuated space in the accumulator. Vacuum is transmitted to the accumulator from a trap which is connected to the accumulator for applying vacuum thereto, Vacuum is established inthe trap by the operation of a vacuum'pump such that only one vacuum pump serves to evacuate the w-hole purifying system. Another conduit leads from the accumulator to the master cylinder or other utilization device so that vacuum is applied to lthe master cylinder via this conduit. After a predetermined time, the impurities have been removed from the liquid, and it is then -transferred to the master cylinder which has already been evacuated. Since the master cylinder is evacuatedalong with the accumulator and tra the cylinder canvbe filled without going through a bleeding*` operation and without exposing'the hydraulic liquid to air in themaster cylinder.

When the cylinder has been filled, a test cycle may be carried out to check the master cylinder for leaks. This is preferably accomplished by the use of a'4 leakage indicator of the type described and claimed in U.S. Patent No. 3,100,986 issued on-August 20, 1963,` to Louis Starr et al., and assigned` to the present assignees.- The leakage indicator includes a pressure differentialV indicator having two sides, a conduit for applying uid pressure to one side of the indicator, another conduit for supplyingiiuid pressure to the other side of the indicator and also to the work to be tested, so that if there is a leak in the work a differential pressure between the first and second conduits will be recorded by the differential pressure indicator. If

ICC

there is no leakage, the pressure on both sides of the indicator will be the same, so the indicator will show no differential pressure.

It is, accordingly, an object of the present invention to providev apurifying system which will reliably remove gaseous impurities from a liquid.

Another object of the invention is to provide a purifying system which exposes a liquid to be purified to vacuum conditions in order to remove gaseous impurities from the liquid.

A further object of the invention is to provide vacuum conditions in different portions of a purifying system by the use of a single vacuum pump.

Another object of the invention is to provide a purifying system which removes impurities from a liquid and which evacuates a utilization device so that the device can be filled with the purified liquid without exposing the liquid to air.

Another object of the invention is to provide a cornbination purifying and leak detecting system for purifying a liquid, filling a utilization device with the liquid, and testing the utilization device for leaks.

Other objects of this invention will appear in the following description and appended claims, refe-rence being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

the drawings:

The single figure of the drawings shows a purification system according tothe invention together with a leakage detector.

Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to b`e` understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

As shown on the drawings:

A utilization device 1, which may be the master brake cylinder of anv automotive vehicle, is to be filled with hydraulic liquid after that liquid has been purified. The hydraulic liquid is supplied from a source 2 which may be a fluidv line or a supply drum. In the embodiment shown, hydraulic oil from the source 2 is admitted to the purification* system through a conduit 3 and a valve 4 which lead to a chamber 53 of a dual hydraulic cylinder and piston combination. This combination includes a large cylinder 6 and a smaller cylinder 7 respectively having a large piston 8 and a smaller piston`9 interconnected by a rod'10. The chamber 5 is filled with hydraulic oil, and enough oil is admitted to fill the systemv upY pa'st valve 20 into the bottom portion of an accumulator 18. g

Vacuum conditions are' established within the accumulator 18 by the operation of a vacuum pump 11. The pumpll is connected v'ia a conduit 12 and' valve 13' to the chamber of atrap'=14", and the trap14` is connected by a coil 16V and conduit 17 to thech'aniber4 of the accumulator 181 Thus, vacuum which is produced in the trap 14 by the vacuumy pump' 11' is transmitted by conduit 17 to' the accumulator'l'S. G'aseous impurities escape from the liquid whichfills the chamber 5 and the lower part ofthe accumulator 18, and these impurities r are removed from the accumulator 18 through conduit 17 to the trap 14 where theyare exhausted from the end 15 of a coil 16. Any liquid contained in the exhausted impurities is discharged from the bottom end of the trap 14, and gaseous material introduced into trap 14 is drawn off by the vacuum pump 11'. Liquid level controls 41' and42 are provided for accumulator 18 and trap 14 respectively to prevent liquids from filling these chambers up to the level of the coils 19 and 16.

The utilization device 1 is also evacuated at the same time that accumulator 18 and trap 14 are evacuated and by the same vacuum pump 11. rThis is accomplished by means of a conduit 22 which connects the utilization device 1 to a coil 19 provided in the accumulator 18. The vacuum in accumulator 18 is transmitted to the utilization device by conduit 22, and gases evacuated from device 1 are discharged into the accumulator 18 and from there to trap 14 and out through the vacuum pump 11. Thus, the utilization device 1, the accumulator 18 and trap 14 are all evacuated by the single vacuum pump 11.

After a predetermined time in which the hydraulic oil in chamber has been purified, valves 4 and 20 close automatically to trap the liquid in chamber 5. This liquid is then pushed out of chamber- 5 by operation of the pistons 8 and 9 which may be advanced by hydraulic pressure. The liquid flows from chamber 5 through a conduit 21 and a valve 23 to a control means 24 which supplies the hydraulic oil under pressure to a leakage detection system 25. It may be noted that the detection system could be bypassed and the oil supplied directly from valve 23 to the utilization device 1. v

The leakage detector 25 includes a differential pressure gauge l26 which has an indicator needle 27, a pressure responsive operator 28 and two inputs 29 and 3G onl opposite sides of the operator 28. One of the inputs 29 is connected to a first liquid conduit 31 which extends between the check valve 32 and the differential guage 26, and the other input 30 is connected to a second conduit`33 which extends between another check valve 34 and the differential guage 26. A pressure differential between conduits 31 and 33 actuates the operator 28 of the differential gauge to defiect the needle 27 from its zero position. If the pressure is the same in conduits 31 and 33, the needle is not deflected and shows no differential pressure.

Hydraulic oil from the purifying system is supplied to the leakage detectorf25 through a check valve 35 and a conduit 36 which is connected to the two check valves 32 and 34. A static pressure gauge 37 is connected to conduit 36 to permit reading of the absolute pressure existing in the leakage detector 25 at the beginning of a testing operation. The absolute pressure may be in the range from two thousand to five thousand pounds per square inch, and the controlrmeans 24 is effective to establish the desired pressure in the system. A manual valve 38 is connected-across conduits 31 and 33 in parallel with the differential gauge 26 and serves to facilitate the filling of the leakage detector with hydraulic oil.

At the beginning of a testing operation, the valve 38 is open. Hydraulic oil from the purifying system is supplied through check valve 3S and conduit 36 to the two conduits 31 and 33 on opposite sides of the differential gauge 26. Hydraulic oil ows from conduit 33 into the utilization device 1 and fills that device with purified hydraulic fluid. The static pressure of this oil is shown by the static gauge 37, but the differential gauge 26 will show a zero reading since there is no difference in the pressure between lines 31 and 33.

When the leakage detector is up to pressure, valve 38 is closed to isolate conduits 31 and 33 from each other. If there is a leak in the utilization device 1, the pressure in conduit 33 will drop, and this will be indicated by a deflection of the needle 27 of the differential gauge 26. If there is no leakage in the utilization device 1,.the needle 27 will not be deflected. After the test is completed, the

detector 2S is disconnected from the utilization device 1,

and pressure in the two conduits 31 `and 33 is equalized by opening valve 38. Valve 39 is closed before the detector is disconnected. Valve 39 may be opened aftervthe detector is disconnected in order to drain the system if this is desired.

Thus, the purifying system of the invention effectively removes gaseous impurities from a liquid, and this is done by exposing the liquid to vacuum conditions which areestablished in multiple portions of the system by the use of a single vacuum pump. The purifying system may be connected directly to a utilization device, or it may be used in combination with a leakage indicator to provide an overall combined purifying and leakage indicating systern. The system is straightforward and reliable in operation, and can be expected to have a long service life.

We claim:

1. A purifying system for removing gaseous impurities from a liquid for filling a utilization device, said purifying system including in combination, liquid supply means for supplying liquid to be purified, an accumulator coupled to said supply means to receive liquid therefrom and to expose such liquid to vacuum conditions therein, a trap, first conduit means coupling said trap to said accumulator for transmitting vacuum therebetween and for discharging into said trap gaseous impurities removed from said liquid in said accumulator, second conduit means for coupling said accumulator to said utilization device for applying vacuum from said accumulator to said utilization device, means separate from said fir'st and second conduit means for coupling said accumulator to said utilization device for supplying purified liquid from said accumulator to said utilization device, and a vacuum pump coupled to said trap for evacuating said trap, and also for evacuating said accumulator via said first conduit means and said utilization device via said second conduit means. Y

2. A purifying system for degassing liquids, comprising liquid supply means for supplying liquid to be purified, storage means coupled to said supply means for temporarily storing a quantity of the liquid to be purified, an accumulator coupled to said storage means for exposing liquid from said storage means to vacuum in said accumulator, work to be evacuated, a trap, a conduit leading from said accumulator to said work to be evacuated, another conduit leading from said accumulator to said trap for discharging in said trap gaseous impurities removed from the liquid in said storage means, a vacuum pump for reducing pressure in said trap, said accumulator and work, a further conduit leading from said trap to said pump so that vacuum pulled by said pump is applied (l) via said further conduit to said trap, (2) via said another conduit to said accumulator, and (3,) via said first-named' conduit to said work, and means for transferring purified liquid from said storage means and said accumulator'to said work after evacuation thereof.

V3. A purifying and pressure testing system including in combination, autilization device to be evacuated and filled with liquid, a pressure differential indicator, liquid supply means, storage means coupled to said liquid supply means for temporarily storing a quantity of liquid to be purified, an accumulator coupled to said storage means to receive liquidtherefrorn and to expose such liquid to vacuum conditions therein, means for applying a vacuum to said accumulator to remove gaseous impurities from said "liquid when provided therein, meansv for transmitting vacuum from said accumulator' to said. utilization device, first conduit means connected to supply purified liquid from said storage means to both sides of said pressure dierential indicator, and second conduity means connected to one side of said indicator and adapted to be connected to said utilization device to admit puritied liquid to said utilization device.

4. The system of claim 3 in which said means for applying vacuum to said accumulator includes a trap, a vacuum pump connected to said trap, and means for transmitting vacuum from said trap to said accumulator.

5,. A purifying and pressure testing system including in combination,l a utilization device to be evacuated and filled with liquid, a pressure differential indicator, liquid supply means for supplying liquid to be purified, storage means coupled to said supply means for temporarily storing a quantity of the liquid to be puriiied, an accumulator coupled to said storage means for exposing liquid from said storage means to vacuum in said accumulator, a trap, a vacuum pump connected to said trap, means for transmitting vacuum from said trap to said accumulator to remove gaseous impurities from said liquid when provided in said accumulator, means for transmitting vacuum from said accumulator to said utilizaton device, first conduit means connected to supply purified liquid from said accumulator to both sides of said pressure differential indicator, and second conduit means connected to one side of said indicator and adapted to be connected to said utilization device to admit purified liquid to said utilization device.

6. A purifying system for removing gaseous impurities from a liquid, said purifying system including in combination, a utilization device to be evacuated and lled with a liquid, a source of said liquid, an accumulator coupled to said source to receive liquid therefrom and to expose such liquid to vacuum conditions therein, means including a trap connected to said accumulator and a vacuum pump connected to said trap for applying a vacuum to said accumulator to remove gaseous impurities from said liquid when provided therein, means for transmitting vacuum from said accumulator to said utilization device so that said utilization device and said accumulator and said trap are all evacuated by the same vacuum pump, and conduit means separate from said transmitting means connected to supply purified liquid from said accumulator to said utilization device.

7. A purifying system for supplying purified liquid to a utilization device, said system including in combination, a source of liquid to be purifed, an accumulator coupled to said source to receive liquid therefrom and to expose such liquid to vacuum conditions therein, means for applying a vacuum to said accumulator to remove gaseous impurities from said liquid when provided therein, means for transmitting vacuum between said accumulator and said utilization device so that said accumulator and said utilization device are evacuated by the same vacuum source, and conduit means separate from said transmitting means adapted to supply purified liquid from said accumulator to said utilization device.

8. The purifying system of claim 7 in which said means for applying a vacuum to said accumulator includes a trap, a vacuum pump connected to said trap for applying vacuum thereto, and conduit means connecting said trap to said accumulator for transmitting vacuum therebetween.

9. -In a purifying syste-m for supplying purified liquid to a utilization device, the combination of liquid supply means, storage means coupled to said liquid supply means for temporarily storing a quantitiy of liquid to be purified, an accumulator coupled to said storage means to receive liquid therefrom and to expose such liquid to vacuum conditions therein, a trap, a vacuum pump coupled to said trap for applying a vacuum thereto, means connecting said trap to said accumulator for transmitting vacuum therebetween, means for connecting said accumulator to said utilization device for transmitting vacuum therebetween, and conduit means separate from said transmitting means adapted to supply purified liquid from said accumulator to said utilization device.

References Cited UNITED STATES PATENTS 2,136,774 11/1938 Hickman 55--55 X 3,059,396 10/1-962 Thees 55-189 REUBEN FRIEDMAN, Primary Examiner. R. W. BURKS, Assistant Examiner. 

1. A PURIFYING SYSTEM FOR REMOVING GASEOUS IMPURITIES FROM A LIQUID FOR FILLING A UTILIZATION DEVICE, SAID PURIFYING SYSTEM INCLUDING IN COMBINATION, LIQUID SUPPLY MEANS FOR SUPPLYING LIQUID TO BE PURIFIED, AN ACCUMULATOR COUPLED TO SAID SUPPLY MEANS TO RECEIVE LIQUID THEREFROM AND TO EXPOSE SUCH LIQUID TO VACUUM CONDITIONS THEREIN, A TRAP, FIRST CONDUIT MEANS COUPLING SAID TRAP TO SAID ACCUMULATOR FOR TRANSMITTING VACUUM THEREBETWEEN AND FOR DISCHARGING INTO SAID TRAP GASEOUS IMPURITIES REMOVED FROM SAID LIQUID IN SAID ACCUMULATOR, SECOND CONDUIT MEANS FOR COUPLING SAID ACCUMULATOR TO SAID UTILIZATION DEVICE FOR APPLYING VACUUM FROM SAID ACCUMULATOR TO SAID UTILIZATION DEVICE, MEANS SEPARATE FROM SAID FIRST AND SECOND DONDUIT MEANS FOR COUPLING SAID ACCUMULATOR TO SAID UTILIZATION DEVICE FOR SUPPLYING PURIFIED LIQUID FROM SAID ACCUMULATOR TO SAID UTILIZATION DEVICE, AND A VACUUM PUMP COUPLED TO SAID TRAP FOR EVACUATING SAID TRAP, AND ALSO FOR EVACUATING SAID ACCUMULATOR VIA SAID 